Pig iron and scrap steel have heretofore been melted in cupola furnaces, and electric arc furnaces and electric induction crucible furnaces.
A cupola furnace has the disadvantage that it requires a solid expensive metallurgical coke having a particle size larger than 40 mm and a low ash content. It is like a small blast furnace and requires equipment for powering and heating its blast.
An arc furnace involves high electrical energy and electrode supply costs and also may involve a high noise level when starting a melting operation.
In the case of an electric induction crucible furnace, there is the problem of the high electric energy expense.
The foregoing shows that there is a need for an improvement on the furnaces now available for the melting of pig iron and scrap.